1. Field of Invention
The present invention relates to a fan and a motor thereof, and in particular to a fan and an inner-rotor motor thereof.
2. Related Art
In the trend of miniaturizing current fan applied to electronic apparatus or system, it is necessary to enhance the heat dissipation efficiency of the fan within the limited volume. To achieve this goal, it is an applicable way to adjust the size of the blade of the fan.
Generally speaking, according to the dispositions of the rotor and stator, the motor of the fan is divided into an outer-rotor motor and an inner-rotor motor. Referring to FIG. 1, a conventional fan 1 includes an inner-rotor motor 10 for driving the blades 14 to rotate. The stator of the fan 1 includes several sets of silicon steel sheet 12 and winding 13. Each set of silicon steel sheet 12 and each winding 13 are disposed between the frame 15 and the blades 14, and the notch of the silicon steel sheet 12 occupies a part of the inner space of the frame 15. Thus, the areas of the outlet and inlet of the fan 1 are restricted, and the air flows of the fan 1 are decreased accordingly. In addition, the windings 13 must be wound on the silicon steel sheets 12 respectively, so that the manufacturing costs are high.